ISO/IEC 27033-4:2014

DRAFT INTERNATIONAL STANDARD ISO/IEC DIS 27033-4
ISO/IEC JTC 1 Secretariat: ANSI

Voting begins on Voting terminates on
2013-01-16 2013-04-16
INTERNATIONAL ORGANIZATION FOR STANDARDIZATION • МЕЖДУНАРОДНАЯ ОРГАНИЗАЦИЯ ПО СТАНДАРТИЗАЦИИ • ORGANISATION INTERNATIONALE DE NORMALISATION
INTERNATIONAL ELECTROTECHNICAL COMMISSION • МЕЖДУНАРОДНАЯ ЭЛЕКТРОТЕХНИЧЕСКАЯ КОММИСИЯ • COMMISSION ÉLECTROTECHNIQUE INTERNATIONALE

Information technology — Security techniques — Network
security —
Part 4:
Securing communications between networks using security
gateways
Technologies de l'information — Techniques de sécurité — Sécurité de réseau —
Partie 4: Sécurisation des communications entre réseaux en utilisant des portails de sécurité
[Revision of first edition (ISO/IEC 18028-3:2005)]
ICS 35.040
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International Organization for Standardization, 2013
©
International Electrotechnical Commission, 2013

ISO/IEC DIS 27033-4
Copyright notice
This ISO document is a Draft International Standard and is copyright-protected by ISO. Except as permitted
under the applicable laws of the user's country, neither this ISO draft nor any extract from it may be
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ii © ISO/IEC 2013 — All rights reserved

ISO/IEC DIS 27033-4
Contents Page
Foreword . iv
Introduction . v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Abbreviated terms . 2
5 Structure . 3
6 Overview . 4
7 Security threats . 5
8 Security requirements . 5
9 Security controls . 7
9.1 Overview . 7
9.2 Packet filtering . 8
9.3 Stateful packet inspection . 9
9.4 Application firewall . 9
9.5 Content filtering . 10
9.6 Intrusion protection system and intrusion detection system. 10
9.7 Security management API . 10
10 Design techniques . 11
10.1 Security gateway components . 11
10.1.1 Switches . 11
10.1.2 Routers . 11
10.1.3 Application level gateway . 11
10.1.4 Security appliances . 12
10.1.5 Monitoring function . 12
10.2 Deploying security gateway controls . 12
10.2.1 Packet filter firewall architecture . 12
10.2.2 Dual-homed gateway architecture . 13
10.2.3 Screened host architecture . 14
10.2.4 Screen subnet architecture . 15
11 Guidelines for product selection . 15
11.1 Overview . 15
11.2 Selection of a security gateway architecture and appropriate components . 16
11.3 Hardware and software platform . 16
11.4 Configuration . 16
11.5 Security features and settings . 17
11.6 Administration capability. 19
11.7 Logging capability . 19
11.8 Audit capability . 19
11.9 Training and education . 19
11.10 Implementation types . 20
11.11 High availability and operation mode . 20
11.12 Other considerations . 20
Bibliography . 21

© ISO/IEC 2012 – All rights reserved iii

ISO/IEC DIS 27033-4
Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that are members of
ISO or IEC participate in the development of International Standards through technical committees
established by the respective organization to deal with particular fields of technical activity. ISO and IEC
technical committees collaborate in fields of mutual interest. Other international organizations, governmental
and non-governmental, in liaison with ISO and IEC, also take part in the work. In the field of information
technology, ISO and IEC have established a joint technical committee, ISO/IEC JTC 1.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of the joint technical committee is to prepare International Standards. Draft International
Standards adopted by the joint technical committee are circulated to national bodies for voting. Publication as
an International Standard requires approval by at least 75 % of the national bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO and IEC shall not be held responsible for identifying any or all such patent rights.
ISO/IEC 27033-4 was prepared by Joint Technical Committee ISO/IEC JTC 1, Information technology,
Subcommittee SC 27, Security techniques.
This first edition cancels and replaces the ISO/IEC 18028-3:2005), which has been technically revised.
ISO/IEC 27033 consists of the following parts, under the general title Information technology — Security
techniques — Network security:
⎯ Part 1: Overview and concepts
⎯ Part 2: Guidelines for the design and implementation of network security
⎯ Part 3: Reference network scenarios – Threats, design techniques and control issues
⎯ Part 4: Securing Communications between networks using security gateways
⎯ Part 5: Securing communications across networks using virtual private networks (VPNs)
⎯ Part 6: Securing IP network access using wireless
(Note that there may be other Parts. Examples of possible topics to be covered by Parts include local area
networks, wide area networks, broadband networks, web hosting, Internet email, and routed access to third
party organizations. The main clauses of all such Parts should be Risks, Design Techniques and Control
Issues.)
iv © ISO/IEC 2012 – All rights reserved

ISO/IEC DIS 27033-4
Introduction
The majority of both commercial and government organizations have their information systems connected by
networks, with the network connections being one or more of the following:
⎯ within the organization.
⎯ between different organizations.
⎯ between the organization and the general public.
Further, with the rapid developments in publicly available network technology (in particular with the Internet)
offering significant business opportunities, organizations are increasingly conducting electronic business on a
global scale and providing online public services. The opportunities include the provision of lower cost data
communications, using the Internet simply as a global connection medium, through to more sophisticated
services provided by Internet Service Providers (ISPs). This can mean the use of relatively low cost local
attachment points at each end of a circuit to full scale online electronic trading and service delivery systems,
using web-based applications and services. Further, the new technology (including the integration of data,
voice and video) increases the opportunities for remote working (also known as teleworking or telecommuting).
Telecommuters are able to keep in contact through the use of remote facilities to access organization and
community networks and related business support information and services.
However, whilst this environment does facilitate significant business benefits, there are new security threats to
be managed. With organizations relying heavily on the use of information and associated networks to conduct
their business, the loss of confidentiality, integrity, and availability of information and services could have
significant adverse impacts on business operations. Thus, there is a major need to properly protect networks
and their related information systems and information. In other words, implementing and maintaining adequate
network security is critical to the success of any organization’s business operations.
In this context, the telecommunications and information technology industries are seeking cost-effective
comprehensive security solutions, aimed at protecting networks against malicious attacks and inadvertent
incorrect actions, thereby meeting the business requirements for confidentiality, integrity, and availability of
information and services. Securing a network is also essential to achieve accurate billing for network
...